The traditional owners are the Miriwoong Gajerrong peoples who have inhabited the area for thousands of years and knew the Ord river as Goonoonoorrang. The dams were built with no consultation with or compensation to the Indigenous traditional owners. The construction of the Ord River Dam was completed in 1971 by the American Dravo Corporation. The dam was officially opened the following year. The dam wall is long, and high. The earth-fill only dam wall at Lake Argyle is the most efficient dam in Australia in terms of the ratio of the size of the dam wall to the amount of water stored. The lake was named after the property it partly submerged, Argyle Downs. Ord River Dam post office opened on 1 March 1969 and closed on 15 November 1971 demonstrating the approximate duration of the construction camp. In 1996, the spillway wall was raised by, which doubled the dam's capacity. Sediment flowing into the dam caused concerns in the mid-1990s that the dam's capacity could be dramatically reduced. By 2006 continual regeneration of the upper Ord catchment appeared to have reduced the amount of sediment inflow. The dam received a Historic Engineering Marker from Engineers Australia as part of its Engineering Heritage Recognition Program.
Geography
Lake Argyle normally has a surface area of about. The storage capacity, to the top of the spillway is. The lake filled to capacity in 1973, and the spillway flowed until 1984. Lake Argyle's usual storage volume is, making it the largest reservoir in Australia. The combined Lake Gordon/Lake Pedder system in Tasmania is larger but is two dams connected by a canal. At maximum flood level, Lake Argyle would hold of water and cover a surface area of. Higher areas have become permanent islands within the lake's area.
Irrigation
Lake Argyle, together with Lake Kununurra, is part of the Ord River Irrigation Scheme. There are currently some of farmland under irrigation in the East Kimberly region. The original plan was for dam water to irrigate rice crop for export to China. However these plans were scuttled as waterfowl, particularly magpie geese ate rice shoots quicker than they could be planted. Other crops are now grown, but Lake Argyle still remains Australia's most under-utilised lake.
The lake, with its surrounding mudflats and grasslands, has been identified by BirdLife International as an Important Bird Area because it supports about 150,000 waterbirds with twelve species being represented in large enough numbers to be considered internationally significant. The mud flats and grasslands are the natural habitat of eight wader species also represented in internationally significant numbers, along with a healthy population of Australian bustards which are considered a "near threatened" species. Birds for which the lake has global importance include magpie geese, wandering whistling-ducks, green pygmy-geese, Pacific black ducks, hardheads, black-necked storks, white-headed stilts, red-capped plovers, Oriental plovers, black-fronted dotterels, long-toed stints and sharp-tailed sandpipers. Common larger-bodied bird species found at the lake include the Australian pelican, black swan, eastern great egret, royal spoonbill, osprey and wedge-tailed eagle. Common smaller-bodied bird species include the spinifex pigeon, peaceful dove, common sandpiper, white-winged tern and budgerigar, while mid-sized bird species include the red-winged parrot, blue-winged kookaburra and barking owl. Some threats identified by the IBA include invasive weed and animal species, such as the cane toad, as well as agricultural uses, free range cattle and feral ungulates that may be over-grazing in the shallow areas around the lake. The IBA recommends that a fence be installed in the important shallows in the south and east to prevent all ungulates from entering those lake areas.
